Speakers
Description
Leptospirosis is an infectious disease caused by pathogens of the genus Leptospira. This
disease becomes a wide-spreading problem in tropical areas including Thailand. A method of
detection which is used nowadays is microscopic agglutination test (MAT) but its detection limit
is so high that it cannot be used to detect pathogens in low concentration samples. To develop
a new method that has lower detection limit, organically modified silica (ORMOSIL)
nanoparticles with encapsulated fluorescent dyes were used. In this research, fluoresecent-
ORMOSIL nanoparticles were synthesized and tagged by antibodies that are specific for
Leptospira. After synthesizing, these nanoparticles were characterized by transmission electron
microscope (TEM) which showed that they are spherical shapes and their average size is 42.4
nm. Moreover, they were analyzed by fourier transform infrared spectroscopy (FTIR) which
reported that there is carboxyl group on their surfaces. Finally, its detection limit is reported as
10 5 cells/ml by observing agglutination with pathogens under fluorescent microscope. According
to this experiment, we can conclude that fluorescent-ORMOSIL nanoparticles are able to be
used as a targeted probe for Leptospira. For future works, we expect to develop this method to
have a multiplex function and to be used as targeted probe for other diseases.
